The kiln company shares the main refractory materials for ceramic kilns: cordierite-mullite series materials are suitable for applications the temperature is low, the working stress is large, and high thermal shock resistance is required. The low-temperature fast-fired kiln slabs, columns, backings, etc. are often made of cordierite-mullite material.
The weakness of cordierite-mullite materials is the lack of high temperature resistance, and the main cause of damage to the slabs is bending creep. The main ways to improve the life of the slab are to reduce the Na2O and CaO content in the material, improve the sintering to increase the firmness of the cordierite particles and the width of the "connection bridge" between the particles, and try to reduce the bending stress. The main cause of damage to the backing plate is thermal shock creep. The measures to improve the thermal shock resistance are: appropriately increase the content of cordierite and control the difference in physical properties between the aggregate and the matrix to form a suitable weakly bonded interface microcracks.
Silicon carbide materials are suitable for occasions the temperature is very high and high working stress, high thermal conductivity and high thermal shock resistance are required. Silicon carbide materials are divided into oxide bonding, reaction sintering and recrystallization silicon carbide materials and nitride bonding. Oxide combined with silicon carbide is a low-end kiln furniture. The porosity of reaction-sintered silicon carbide is almost zero, and it has high strength, but the use temperature should be higher than 1350 ℃. It is very suitable for low-temperature fast-fired kilns. , Suitable for occasions the temperature is higher than 1350 ℃. The use of chloride combined with silicon carbide varies greatly depending on purity, mineral composition and microstructure. For example, the combination of high purity, granular and dense silicon nitride-silicon oxynitride silicon carbide materials can generate a dense and high viscosity surface glaze layer and an internal protective layer that inhibits oxidation during use, thus a satisfactory service life.
The materials of mullite-corundum series are suitable for occasions with high calcination temperature, such as sintered alumina ceramics and ferrite ceramics.
